1. Field of the Invention
The present invention relates to a small-size light-weight gas turbine driven power system with reduced noise, wherein auxiliary devices driven by a gas turbine, such as a generator, a hydraulic pump and an air compressor, are connected to the gas turbine and all the air introduced into the system is subjected to heat exchange for cooling the inside of the system effectively.
2. Description of the Prior Art
Diesel engine generator systems were widely used as the commercial electric power supplies in solitary islands, outlying mountainous regions, etc. and as the emergency electric power supplies in office buildings, hospitals, plants, etc. The diesel engine generator system has the high thermal efficiency and is short in start-up time and easy to handle.
However, the diesel engine generator system is large in size and heavy in weight and, since a cooling tower filled with cooling water is required, the whole structure thereof is realized on a large scale.
In view of this, gas turbine generator systems which are smaller in size and require no cooling water have been widely used lately instead of the diesel engine generator systems. In the gas turbine generator system, cooling is carried out through heat exchange with the open air introduced into the system, instead of the cooling water used in the diesel engine generator system.
JP-A-5-248263 describes the gas turbine generator system of one type. Specifically, the described gas turbine generator system is provided with, besides an air inlet for introducing the open air for combustion, a ventilation inlet for introducing the open air for cooling the inside of the system. The gas turbine generator system of this type requires the two open air inlets as noted above and thus further requires a plurality of air passages in the system corresponding to the two inlets, hence leading to a complicated inside structure of the system.
JP-A-61-49134 describes the gas turbine generator system of another type which has only one open air inlet. Specifically, as shown in FIG. 3, the system comprises a package shell 100 wherein a gas turbine 101 and a generator 102 are disposed. An air inlet 103 is provided at the front side of the package shell 100, while an exhaust joint duct 104 is provided at the rear side thereof.
An intake pipe 105 forms a passage for the open air sucked via the air inlet 103. A baffle plate 106 is suspended from the underside of the intake pipe 105 for baffling the open air introduced onto the generator 102.
In the intake pipe 105, a plurality of sound absorbing plates 107 are disposed in parallel to each other to form splitters 108 which are arranged in two stages.
A first opening 109a is provided between the first-stage splitter 108 and the second-stage splitter 108 for allowing a portion of the open air flowing in the intake pipe 105 to flow downward as a first air flow A1 for cooling the generator 102.
An intake duct 109b is coupled to the intake pipe 105 at a second opening 110 formed in the neighborhood of a downstream end of the intake pipe 105 for feeding the air, flowing downward via the second opening 110 as a second air flow A2, into the gas turbine 101.
An oil cooler 111 is disposed at the downstream end of the intake pipe 105 and connected to the gas turbine 101 via a lubricant pipe arrangement 112 in which lubricating oil is circulated. The oil cooler 111 cools the oil which becomes high in temperature by cooling the heat generated in a combustor 101a of the gas turbine 101. Specifically, when the air flowing in the intake pipe 105 passes through the oil cooler 111, the oil is cooled by the air.
The foregoing first air flow Al is deflected downward by a blocking plate 113 and introduced into the exhaust joint duct 104 via a vent hole provided downward of the blocking plate 113.
The exhaust joint duct 104 comprises an exhaust pipe 115 of the gas turbine 101, a diffuser 116 and an outlet 117. In the exhaust joint duct 104, the combustor 101a and the exhaust pipe 115 of the gas turbine 101 are projected and the diffuser 116 Is located adjacent thereto.
The diffuser 116 is projected into a flue 118 incorporating therein a muffler (not shown). The first air flow A1 and the third air flow A3 together with exhaust gas from the exhaust pipe 115 are sucked due to an ejector effect provided by the diffuser 116, then flow through the flue 118 and are discharged via the outlet 117 incorporating therein a soundproof mechanism.
With the foregoing structure, when the gas turbine 101 is operated, the generator is driven to produce an electric power supply of about 150 kw to 20,000 kw.
However, in the foregoing conventional gas turbine generator system shown in FIG. 3, a portion of the open air having passed the first-stage splitter 108 is used for cooling the generator 102, then a portion of the open air having passed the second-stage splitter 108 is fed to the gas turbine 101 for combustion, and then only a small amount of the remainder open air is used for cooling the lubricating oil for the gas turbine 101. Thus, cooling effects achieved in the package shell 100 are quite small. This causes the necessity of providing a plurality of air passages in the package shell 100, leading to an increase in size of the gas turbine generator system.
JU-A-56-77618 describes the gas turbine generator system of still another type as shown in FIG. 4. In this system, an oil cooler 111 carries out heat exchange using the air sucked into a gas turbine 122a, so that the heat exchange efficiency is improved from this aspect. However, the inside of the system is divided into a generator room 121 having therein a generator 12 la and an engine room 122. having therein a gas turbine 122a, by means of a partition plate 120, and the air introduced into the system is divided so as to be supplied into the two rooms separately. Therefore, the flow rate of the air passing through the oil cooler 111 is reduced correspondingly, and hence, the heat exchange efficiency is not so enhanced as expected.